The invention relates to a starting method for internal combustion engines in motor vehicles, with a start-stop system and to a starting device for carrying out the method.
Internal combustion engines of motor vehicles are customarily turned on by means of a starter motor, wherein first of all a pinion of the starting device meshes in a ring gear of the internal combustion engine before the starter motor is switched on. In addition, with a start-stop system in motor vehicles, if the motor vehicle has stopped for a relatively long time, the internal combustion engine is automatically switched off and, at the end of the stop phase, the engine is then started again automatically in order to be able to continue the journey.
It is known from EP 08 48 159 A1 to bring starter pinions into the meshed position right at the beginning of a stop state of the engine in order subsequently, at the beginning of the starting operation, to immediately switch on the starter motor at full power. This significantly reduces the time for the starting operation. However, this solution still has the disadvantage that, for the meshing of the starter pinion at the beginning of the stop phase, it is necessary to wait first until the engine is at a standstill, this meaning, if the stop phases are very short, a delay which may be critical, for example in a traffic jam because of vehicles following too closely.
In order to shorten the meshing operation at the beginning of a stop phase, it has already been proposed using electronic activation of the starter motor to synchronize the rotational speed of the pinion with the rotational speed of the ring gear of the engine, in order thereby for the starter pinion to already be meshed in the still rotating ring gear of the engine. A disadvantage here is that, in order to synchronize the circumferential speed of the ring gear and of the starter pinion, a considerable electronic outlay on control has to be expended, since the circumferential speed of the ring gear changes greatly due to compressions in the engine cylinders when the switched-off internal combustion engine comes to a stop.